“A cloth mask or surgical mask protects others from droplets the wearer might expel, but a respirator mask protects the wearer by filtering out smaller particles that might carry the virus,” said civil and environmental engineering Thanh “Helen” Nguyen, who with Vishal Verma published their findings in the journal Environmental Science and Technology Letters.
“There are many different ways to sterilize something, but most of them will destroy the filtration or the fit of an N95 respirator,” Verma said. “Any sanitation method would need to decontaminate all surfaces of the respirator, but equally important is maintaining the filtration efficacy and the fit of the respirator to the face of the wearer. Otherwise, it will not offer the right protection.”
Nguyen and Verma found the dry heat of the electric cooker maintained at 212 F for 50 minutes “decontaminated the masks, inside and out, from four different classes of virus, including a coronavirus — and did so more effectively than ultraviolet light.”
This method used no chemicals and left no residue. The professors noted there can be no water in the cooker, and the masks should not touch the inside. However, numerous masks can be stacked inside and sterilized at the same time.
Not only were the masks decontaminated, but they also “maintained their filtration capacity of more than 95% and kept their fit, still properly seated on the wearer’s face, even after 20 cycles of decontamination in the electric cooker,” Verma said.
The professors created a video for anyone wanting to use this method at home.